Volatile compounds in Shochu were analyzed by headspace method in most cases. But there was no report about gas chromatography using olfactory organ. So we carried out the investigation of volatile compounds and aroma-active compounds of cereal Shochu, especially buckwheat Shochu. Volatile flavor fractions were concentrated from buckwheat, rice and barley Shochu by porapak Q column method (solid-phase extraction). Those concentrated samples were then analyzed by gas chromatography olfactometry (GC-O), aroma extract dilution analysis (AEDA) method and gas chromatography/mass spectrometry (GC/MS). Twenty-one, 14 and 18 of volatile compounds were newly identified from buckwheat, rice and barley Shochu, respectively. Aroma-active compounds of buckwheat, rice and barley Shochu were identified, 22, 20 and 23, respectively. We found that most of aroma-active compounds of buckwheat Shochu have higher flavor dilution (FD) factors than that of other Shochu by AEDA method. Particularly we might guessed that ethyl cinnamate contained in buckwheat Shochu had low odor threshold value and was one of important aroma-active compounds. We found that unknown characteristic flavor of buckwheat Shochu existed in basic action by pH fractionation method and GC-O.

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The activities of food-related hydrolyzing enzymes (subtilisin, -amylase, and lipase) were examined in electrolyzed water samples obtained by electrolyzing NaCl (100mg/l) solution. Subtilisin (5mg) dissolved in the electrolyzed cathode water of pH 10 (100ml), followed by incubation for 10min at 60°C, showed the activity increased by about 80%. The key factor for this positive result was the influence on subtilisin of both Na⁺ ion condensed by electrolysis and pH changed during electrolysis, which resulted in raising the maximum activity and the optimal temperature. Also, the effect of electrolyzed cathode water was found to depend on the preparations of subtilisin. After mixing α-amylase (85mg) and the electrolyzed cathode water (pH 11) (100ml), followed by incubation for 10min at 37°C, the activity of α-amylase increased by 20%. This is mainly because the turnover number and solubility of α-amylase improved by the electrolyzed water. After mixing lipase (10mg) and the electrolyzed anode water (pH 3) (10ml), followed by incubation for 30min at 30°C, the activity of lipase increased by 22%. This was found to be due to the Cl^- ion concentrated by electrolysis and pH as well as other factors that were not clearly identified.

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Resveratrol (RT) is one of the major stilbene phytoalexins found in several plants, including grapevines and the peanut (Arachis hypogaea L.). It is produced by the plants as a defense response to some exogenous stimuli, particularly fungal challenges. RT is attracting attention, because it has been associated with reduced cardiovascular diseases and cancer risks. We analyzed concentrations of RT in seeds and seed coats of peanut cultivars cultivated in Japan and peanut products, by using HPLC. Seeds from three kinds of Japanese peanut cultivars, Chibahandachi, Nakateyutaka and Satonoka contained from 0.089 to 0.147μg of trans-RT/g, while in seeds coats from same cultivars the concentrations were from 5.55 to 6.91μg/g, which were much higher than the figures reported so far. Roasted peanuts and fried peanuts contained trans-RT from 0.033 to 0.085μg/g and trans-RT from 0.038 to 0.072μg/g respectively, and Japanese sweetened peanuts, Amanatto and Rakkato contained trans-RT of 0.043μg/g and 0.035μg/g, respectively.

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The objective of this study was the identification of the volatile compounds in porcine liver to clarify the key compounds of fishy off-flavor. The volatile compounds of liver sample with and without ferrous chloride were collected using steam distillation under reduced pressure and the volatiles were analyzed by GC and GC-MS. Volatile aldehydes, alcohols and acids in porcine liver added with ferrous chloride increased in kinds and amounts. Results showed that (E, Z)-2, 4-heptadienal, (E, E)-2, 4-heptadienal which possibly contribute to the fishy off-flavor were considered to have been produced from unsaturated fatty acids of porcine liver by oxidation.

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An alkaline protease inhibitor-inactivating enzyme (AIE) of Aspergillus oryzae W-1 was purified to homogeneity by the combination of various column chromatographies. The molecular mass of the enzyme was estimated to be 42 kDa by SDS-PAGE; the isoelectric point was 4.7. AIE was optimally active at around 55°C and pH6. The enzyme was stable up to 40°C and in the pH range of 6-10. AIE was inactivated by HgCl₂ or p-chloromercuribenzoate (p-CMB) but not by trypsin inhibitor, leupeptin, and phenylmethylsulfonylfluoride (PMSF). It was also inactivated by chelating agents, like ethylenediaminetetraacetate (EDTA) and o-phenanthroline. The enzyme treated with HgCl₂, however, was reactivated by the addition of 2-mercaptoethanol (2-ME). On the other hand, EDTA-inactivated AIE was reactivated in the presence of 2-ME and CaCl₂. When the protease-inhibitor complex was incubated with AIE at 37°C and pH5, the activation of AP was detected. From these results, it was supposed that AIE is responsible for the activation of alkaline protease (AP) in the cells of mold.

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The texture of 112 food samples was characterized and classified by means of multi-variance analysis, in order to obtain one index of chewing instruction. The texture of food samples was measured by Tensipresser. Characterization and classification of foods was performed from principal component analysis of the texture of food. Food samples with higher chewiness (1.00 or more) relevant to masticatory muscle activities were 30% or less. By means of principal component analysis, 111 of food sample investigated were classified into nine food groups as follows. Basic food sample group: hardness and springiness are low. Group I foods: hardness is high, Group II foods: hardness and springiness are high. Group III foods: springiness is high. Group I was further classified into two sub-groups. Group II and III were further classified into three sub-groups. Some food samples with higher chewiness were belonged to Group I-2 and Group II-1, 2, 3.

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